Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-23T18:20:20.008Z Has data issue: false hasContentIssue false
  • English
  • Français

The reversibility of constraints on size and fecundity in the parasitic nematode Strongyloides ratti

Published online by Cambridge University Press:  04 July 2006

M. E. VINEY ,
M. D. STEER  and
C. P. WILKES
M. E. VINEY
Affiliation:
School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
M. D. STEER
Affiliation:
School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
C. P. WILKES
Affiliation:
School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

The size and fecundity of parasitic nematodes are constrained by the host immune response. For the parasitic nematode of rats, Strongyloides ratti, parasitic females infecting immunized rats are smaller and less fecund than those infecting naïve rats. Here, we investigated whether these constraints on size and fecundity are life-long. This was done by comparison of worms from different immunization and immunosuppression regimes. It was found that the per capita fecundity of parasitic females of S. ratti is fully reversed, but that their size is only partially reversed, if previously immunized hosts are subsequently immunosuppressed, suggesting that fecundity is not subject to life-long constraints. The host immune response also resulted in allometric changes in the parasitic females. The significance of these results with respect to the growth and control of nematode fecundity are discussed.

Keywords

sizefecundityimmune pressureallometry
Type
Research Article
Information
Parasitology , Volume 133 , Issue 4 , October 2006 , pp. 477 - 483
Copyright
© 2006 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Bell, R. G., Adams, L. S. and Gerb, J. ( 1981). Strongyloides ratti: Dissociation of the rat's protective immunity into systemic and intestinal components. Experimental Parasitology 52, 386–395.CrossRefGoogle Scholar
Crook, M. and Viney, M. E. ( 2005). The effects of non-immune stresses on the development of Strongyloides ratti. Parasitology 131, 383–392.CrossRefGoogle Scholar
Flemming, A. J., Shen, Z-Z., Cunha, A., Emmons, S. W. and Leroi, A. M. ( 2000). Somatic polyploidization and cellular proliferation drive body size evolution in nematodes. Proceedings of the National Academy of Sciences, USA 97, 5285–5290.CrossRefGoogle Scholar
Gemmill, A. W., Viney M. E. and Read A. F. ( 1997). Host immune status determines sexuality of a parasite nematode. Evolution 51, 393–401.CrossRefGoogle Scholar
Kimura, E., Shintoku, Y., Kadosaka, T., Fujiwara, M., Kondo, S. and Itoh, M. ( 1999). A second peak of egg excretion in Strongyloides ratti-infected rats: its origin and biological meaning. Parasitology 119, 221–226.CrossRefGoogle Scholar
Knight, C. G., Azevedo, R. B. R. and Leroi, A. M. ( 2001). Testing life-history pleiotropy in Caenorhabditis elegans. Evolution 55, 1795–1804.CrossRefGoogle Scholar
Leroi, A. M. ( 2001). Molecular signals versus the Loi de Balancement. Trends in Ecology and Evolution 16, 24–29.CrossRefGoogle Scholar
Mitreva, M., McCarter, J. P., Martin, J., Dante, M., Wylie, T., Chiapelli, B., Pape, D., Clifton, S. W., Nutman, T. B. and Waterston, R. H. ( 2004). Comparative genomics of gene expression in the parasitic and free-living nematodes Strongyloides stercoralis and Caenorhabditis elegans. Genome Research 14, 209–220.CrossRefGoogle Scholar
Moqbel, R. and McLaren, D. J. ( 1980). Strongyloides ratti: Structural and functional characteristics of normal and immune-damaged worms. Experimental Parasitology 49, 139–152.CrossRefGoogle Scholar
Moqbel, R., McLaren, D. J. and Wakelin, D. ( 1980). Strongyloides ratti: Reversibility of immune damage to adult worms. Experimental Parasitology 49, 153–166.CrossRefGoogle Scholar
Nyström, J., Shen, Z-Z., Aili, M., Flemming, A. J., Leroi, A. and Tuck, S. ( 2002). Increased or decreased levels of Caenorhabditis elegans lon-3, a gene encoding a collagen, cause reciprocal changes in body length. Genetics 161, 83–97.Google Scholar
Parkinson, J., Mitreva, M., Hall, N., Blaxter, M. and McCarter, J. P. ( 2003). 400000 nematode ESTs on the net. Trends in Parasitology 19, 283–286.CrossRefGoogle Scholar
Paterson, S. and Viney, M. E. ( 2002). Host immune responses are necessary for density dependence in nematode infections. Parasitology 125, 283–292.CrossRefGoogle Scholar
Quinn, G. and Keough, M. ( 2002) Experimental Design and Data Analysis for Biologists. Cambridge University Press, Cambridge.
Skorping, A, Read, A. F. and Keymer, A. E. ( 1991). Life history covariation in intestinal nematodes of mammals. Oikos 60, 365–372.CrossRefGoogle Scholar
Stear, M. J., Bairden, K., Duncan, J. L., Holmes, P. H., McKellar, Q. A., Park, M., Strain, S., Murray, M., Bishop, S. C. and Gettinby, G. ( 1997). How hosts control worms. Nature, London 289, 27.CrossRefGoogle Scholar
Suzuki, Y., Yandell, M. D., Roy, P. J., Krishna, S., Savage-Dunn, C., Ross, R. M., Padgett, R. W. and Wood, W. B. ( 1999). A BMP homolog acts as a dose-dependent regulator of body size and male tail patterning in Caenorhabditis elegans. Development 126, 241–250.Google Scholar
Thompson, F. J., Mitreva, M., Barker, G. L., Martin, J., Waterston, R. H., McCarter, J. P. and Viney, M. E. ( 2005). An expressed sequence tag analysis of the life-cycle of the parasitic nematode Strongyloides ratti. Molecular and Biochemical Parasitology 142, 32–46.CrossRefGoogle Scholar
Tindall, N. R. and Wilson, P. A. G. ( 1988). Criteria for a proof of migration routes of immature parasites inside hosts exemplified by studies of Strongyloides ratti in the rat. Parasitology 96, 551–563.CrossRefGoogle Scholar
Viney, M. E. ( 2002). How do host immune responses affect nematode infections? Trends in Parasitology 18, 63–66.Google Scholar
Wilkes, C. P., Thompson, F. J., Gardner, M. P., Paterson, S. and Viney, M. E. ( 2004). The effect of the host immune response on the parasitic nematode Strongyloides ratti. Parasitology 128, 661–669.CrossRefGoogle Scholar